According to reports, the trawler refused to leave, which led to a confrontation and the Spanish police boat getting involved. Royal Navy sailors then “read out a sovereignty warning to leave Gibraltar waters immediately” and the trawler left.

A Royal Navy spokesperson confirmed to the Daily Mail that the incident took place, saying: “This is nothing unusual. These things happen often.

“It is another territorial display, similar to what we have seen in Gibraltar over the past years.”

Gibraltar, a British Overseas Territory situated on Spain’s southern tip, has been in British hands for more than 300 years. Known to its 30,000 residents as ‘The Rock’, the territory remains a major source of diplomatic tension.

In the EU referendum, its 30,000 residents voted overwhelmingly to stay in the bloc, with 96 percent voting to remain.

Questions over the post-Brexit future of Gibraltar have arisen since the EU inserted a clause in its Brexit negotiation position allowing Spain to veto any Brexit deal involving Gibraltar, potentially putting Britain’s sovereignty over ‘the Rock’ at stake.